before streaking across southern russia. cameras caught sight of the white trail as it headed across the sky. and then this. an explosion of light, then a massive sonic boom. strong enough to shatter windows and damage buildings. there were reports of more than 1,000 people injured. mostly from glass and debris. this video shows a children's judo class. windows blew out here and in buildings around the region. some people said they thought it might have been a plane crash. this is the aftermath of the blast in a high school. a 17-year-old student put this video on youtube, showing the reaction in his physics class. students screamed and ran into the hallways. he said some in the class thought war had started. some of the incredible images were caught on cameras placed inside russian cars. many drivers now record their journeys in case of crashes or run-ins with police. shock and gasps at the blinding light, the boom, and all the shattered glass. jim bolden, cnn, london. >> amazing. let's dig in a little deeper with physicist